Sicilian Defense: Smith-Morra Gambit Accepted, Chicago Defense (7. O-O a6)
1. e4 c5 2. d4 cxd4 3. c3 dxc3 4. Nxc3 d6 5. Nf3 e6 6. Bc4 Nf6 7. O-O a6
The Sicilian Defense: Smith-Morra Gambit Accepted, Chicago Defense is a chess opening classified as ECO B21, reached after 1. e4 c5 2. d4 cxd4 3. c3 dxc3 4. Nxc3 d6 5. Nf3 e6 6. Bc4 Nf6 7. O-O a6. It is a line of the Sicilian Defense. White is to move.
In 12.6 million rated Lichess games (blitz and slower), this position was reached 10 times by this move order. White won 50%, 10% were drawn and Black won 40%. The most popular continuation is 8. Qe2 (70% of games).
Engine evaluation: 0.00 (Stockfish, depth 43; best line 8. e5 dxe5 9. Qxd8+ Kxd8 10. Nxe5 Ke8)
- ECO
- B21
- Moves
- 14 plies
- FEN
rnbqkb1r/1p3ppp/p2ppn2/8/2B1P3/2N2N2/PP3PPP/R1BQ1RK1 w kq - 0 8- PGN
1. e4 c5 2. d4 cxd4 3. c3 dxc3 4. Nxc3 d6 5. Nf3 e6 6. Bc4 Nf6 7. O-O a6
Analyse with Stockfish · Board image (SVG) · Open on Lichess
Results by rating
| Average rating | Games | White / draw / Black |
|---|---|---|
| 1500-1999 | 6 | |
| 2000+ | 4 | |
| All | 10 |
Most played moves
| Move | Games | White / draw / Black |
|---|---|---|
| 8. Qe2 | 7 (70%) | |
| 8. Be3 | 1 (10%) | |
| 8. a4 | 1 (10%) | |
| 8. Bg5 | 1 (10%) |
Master games
1 over-the-board game is classified under this line (White 0%, draw 0%, Black 100%). The strongest:
- FM Ariel Pulido Alvarez (2252) – Vepaly Halynyazov (2195) 0-1 · Titled Tue 3rd Mar 2026 · 2026-03-03
Highest-rated Lichess games
- Abishan99 (2178) – krapiwa2025 (2173) 1-0 · 2026-09-01 · 180 + 0s
- s_1704 (2168) – knimusbis (2068) 1-0 · 2026-09-01 · 180 + 0s
- Romio40 (2050) – riquelme3579 (2078) 0-1 · 2026-09-07 · 180 + 0s
Comes from
Sicilian Defense: Smith-Morra Gambit Accepted 1. e4 c5 2. d4 cxd4 3. c3 dxc3
More Sicilian Defense lines (all)
- Sicilian Defense (1. e4 c5) B20
- Sicilian Defense: Amazon Attack B20
- Sicilian Defense: Big Clamp Formation B20
- Sicilian Defense: Bowdler Attack B20
- Sicilian Defense: Brick Variation B20
- Sicilian Defense: Czerniak Attack B20
- Sicilian Defense: Czerniak Attack, Queen Fianchetto Variation B20
- Sicilian Defense: Euwe Attack, Prins Gambit B20
- Sicilian Defense: Gloria Variation B20
- Sicilian Defense: Grob Variation B20
- Sicilian Defense: Keres Variation B20
- Sicilian Defense: King David's Opening B20
Opening names and moves from the Lichess openings dataset; statistics from the Lichess open database, 2026-09 (CC0), sample of 12.6 million games, bots excluded; evaluations from Lichess cloud analysis (all CC0). Master games from The Week in Chess #920–#1664 by Mark Crowther, used with permission.